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Byline: Ge. Mingjian, Shi. De, Wu. Qingchen, Wang. Mei, Li. Liangbin Background and Aims: The failure to reduce the mortality of patients with solid tumours is mainly a result of [...]

Blends of polypropylene (PP) with a copolymer of ethylene and octene (EOC) were studied. The effect of viscosity ratio of elastomer domains to the matrix PP ηd/ηm (where subscript d and m designate dispersed phase and matrix, respectively) on fibril formation was investigated. Fibril morphology was observed for both ηd/ηm ≈ 1 and ηd/ηm > 1 (ηd/ηm = 1.70 or 2.40). As the viscosity ratio increased further, the spherical, elliptical, and rodlike morphology appeared. Fibril formation at ηd/ηm > 1 is possibly attributed to the effect of the interface interaction between the two phases. With soft fibril formation of EOC in PP, mechanical properties of the blends such as tensile and flexural properties were not improved and the impact strength was low compared to those of blends with spherical, elliptical, and rodlike dispersed morphology. © 2002 John Wiley & Sons, Inc. J Appl Polym Sci 83: 1870–1874, 2002

The high-pressure crystallized poly(ethylene terephthalate) samples were investigated with scanning electron microscopy. The striation appearance, which is the most common feature of polymer extended-chain crystals, was clearly observed. Poly(ethylene terephthalate) extended-chain crystals with thickness up to 17 m were obtained at high pressure. Fibrous crystals were also formed at high pressure. The fracture behaviors, which affected the exposure of the striations, were also discussed. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1612–1616, 2000